PIC32DIP Breakout Board design overview
New PIC32s that come in DIP28 packages are simple to prototype with, and now we made them even simpler. This breakout board has all the suport circutry you need for the microcontroller alowing you to concentrate on the rest of your project. It features:
- USB and external 3.3V regulated power-supply
- USB connector
- 8 MHz crystal
- Reset button
- Programing ICSP header
- All the port pins broken out to two rows of headers for easier use with standard breadboards
You can get a [project for $20], including worldwide shipping.
History and related links
The breakout board is built around the PIC32MX220F032B microcontroller that comes in the PDIP28 package. Each power pin is decoupled with a 0.1uF capacitor (C1, C4, and C9), while the internal voltage regulator PIN (VCAP) is supplied with a 10uF capacitor (C2)
The board features a 3.3V voltage regulator (VR1) that can be powered either through the USB or an external 5V supply via the 2.1mm barrel jack. The voltage regulator requires two 1uF capacitors, one (C8) on the input, and one (C7) on the output.
A quartz crystal (XTAL1) oscillator with two load capacitors (C5 and C6) provides a stable source for the microcontroller's CPU, and USB clocks.
The ICSP programing connection is brought to a header for easy development. The MCLR (RESET) programming pin is connected to the power supply through a 10K pull-up resistor (R1). Thus keeping the PIC in reset until the power supply is satisfactory.
All the pins except the primary oscillator ones (RA2 and RA3) are borken out into two rows of headers. They are labeled by their port numbers for quick reference.
There are two configurations for soldering on the pins. It depends weather your uC has USB support or not.
If USB is supported, then don't solder the two header pins marked as RB10,RB11, and RB12 they are connected to the D+, D-, 3.3v lines used by the USB. Also solder up the solder jumper SJ1.
Not using USB frees up the 3 extra pins for your project so solder RB10-RB12, and leave the solder jumper unconnected.
- PCB and placement notes
- soldering advise
Click for a full size placement image.
- Operating modes
- extra software required
We used the Microchip USB stack to run the 18F2550 as a virtual serial port. Microchip's code is open but not redistributable. If you want to compile the source, download the stack from Microchip, then drag the source code into the install directory. See the detailed instructions in the PIC compiler how-to.
The virtual serial port (CDC) is an open standard, it should work on any modern operating system.
You don't need a driver, but you will need a .inf file to tell Windows how to use the device. A suitable .inf is included in the project archive.
Source and license
Taking it further
Here's some ideas for the future:
We'll post the most recent firmware updates on our blog. You can also join the discussion in the [forum].
You can [get one for $00], including worldwide shipping.
Your purchases at Seeed Studio keep the open source project coming, we sincerely appreciate your support!